1. Field of the Invention
The present invention relates to a marine propulsion system for a watercraft. More particularly, this invention involves a system of rotating foil blades forming a water turbine propeller which generates efficient propulsion at a low rate of revolution.
2. Description of the Related Art
The prior art, as is known to the inventor, consists of turbines, vessels, or marine propulsion system, which conduct water through conduits for propulsion, or actual turbine jets.
U.S. Pat. No. 5,451,137 teaches a reaction turbine and more specifically two unidirectional reaction turbines operable under reversible fluid flows for use with hydro-pneumatic, hydro, wind, or wave power systems. The hydro-pneumatic power systems are used for generating power from tidal or current motion of water. This invention provides a unidirectional reaction turbine capable of achieving high speeds needed for industrial electric generators under ultra-low head pressure fluid flow and/or flows of velocities of 5 feet per second or greater. Further, this invention has air-foil shaped blades connected to supporting members that are mounted on a rotatable shaft.
U.S. Pat. No. 5,722,864 teaches a marine propulsion system for watercraft. The system has propulsion blades internal to the housing of the system as opposed to externally, such as with a typical marine propeller.
U.S. Pat. No. 6,470,817 teaches additional improvements in small waterplane area multihull (SWAMH) vessels. The vessel includes an engine means that is situated on the upper hill platform and is joined to the rotary propulsive means which converts the output of the engine to the rotary motion to provide a propulsive force.
U.S. Pat. No. 7,902,687 teaches a submersible turbine-generator unit for ocean and tidal currents. More specifically, the submersible turbine-generator will create hydroelectric power, which is a source of renewable energy.
U.S. Pat. No. 8,061,993 teaches a vertical axis turbine for unidirectional rotation under multidirectional fluid flows for use with hydro-pneumatic, hydro, wind, or wave power systems. The vertical axis turbine is particularly suited for fluid flows that will naturally change direction while remaining parallel to the surface from which the rotating shaft of the vertical axis turbine extends. The turbine does not need to be placed in a channel for directing fluid flow in a specific direction across its blades.